MethodType parameter names not retained (#5923)

* MethodType parameter names not retained for Guava method

* Show a possible solution with reflection by Claude

* Remove special handling for int/String

* Pass in `-parameters` instead

* Revert formatting changes

* Replicate change to other Java parser versions

* Move test method and use assertj-core which is already present

* Revert to `get(0)` when running on Java 8, 11 & 17

* Only enable test on Java 11+ for now

* Minimize accidental changes between Java 8 and 11 parsers

* Apply suggestions from code review

Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>

---------

Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>

Author: timtebeek

rewrite-java-11/src/main/java/org/openrewrite/java/isolated/ReloadableJava11Parser.java

@@ -109,6 +109,7 @@ private ReloadableJava11Parser(
         // https://docs.oracle.com/en/java/javacard/3.1/guide/setting-java-compiler-options.html
         Options.instance(context).put("-g", "-g");
         Options.instance(context).put("-proc", "none");
+        Options.instance(context).put("-parameters", "true");
 
         // Ensure type attribution continues despite errors in individual files or nodes.
         // If an error occurs in a single file or node, type attribution should still proceed

rewrite-java-11/src/main/java/org/openrewrite/java/isolated/ReloadableJava11ParserVisitor.java

@@ -467,7 +467,7 @@ public J visitClass(ClassTree node, Space fmt) {
 
         List<Tree> membersMultiVariablesSeparated = new ArrayList<>(node.getMembers().size());
         for (Tree m : node.getMembers()) {
-            // skip lomobok generated trees
+            // skip lombok generated trees
             if (isLombokGenerated(m)) {
                 continue;
             }
@@ -1938,7 +1938,6 @@ private static boolean isLombokGenerated(Tree t) {
         Tree tree = (t instanceof JCAnnotation) ? ((JCAnnotation) t).getAnnotationType() : t;
 
         Symbol sym = extractSymbol(tree);
-
         if (sym == null) {
             // not a symbol we can check
             return false;

rewrite-java-17/src/main/java/org/openrewrite/java/isolated/ReloadableJava17Parser.java

@@ -109,6 +109,7 @@ private ReloadableJava17Parser(
         // https://docs.oracle.com/en/java/javacard/3.1/guide/setting-java-compiler-options.html
         Options.instance(context).put("-g", "-g");
         Options.instance(context).put("-proc", "none");
+        Options.instance(context).put("-parameters", "true");
 
         // Ensure type attribution continues despite errors in individual files or nodes.
         // If an error occurs in a single file or node, type attribution should still proceed

rewrite-java-21/src/main/java/org/openrewrite/java/isolated/ReloadableJava21Parser.java

@@ -109,6 +109,7 @@ private ReloadableJava21Parser(
         // https://docs.oracle.com/en/java/javacard/3.1/guide/setting-java-compiler-options.html
         Options.instance(context).put("-g", "-g");
         Options.instance(context).put("-proc", "none");
+        Options.instance(context).put("-parameters", "true");
 
         // Ensure type attribution continues despite errors in individual files or nodes.
         // If an error occurs in a single file or node, type attribution should still proceed

rewrite-java-8/src/main/java/org/openrewrite/java/ReloadableJava8Parser.java

@@ -102,6 +102,7 @@ class ReloadableJava8Parser implements JavaParser {
         // https://docs.oracle.com/en/java/javacard/3.1/guide/setting-java-compiler-options.html
         Options.instance(context).put("-g", "-g");
         Options.instance(context).put("-proc", "none");
+        Options.instance(context).put("-parameters", "true");
 
         // Ensure type attribution continues despite errors in individual files or nodes.
         // If an error occurs in a single file or node, type attribution should still proceed

rewrite-java-8/src/main/java/org/openrewrite/java/ReloadableJava8ParserVisitor.java

@@ -520,7 +520,6 @@ public J visitCompilationUnit(CompilationUnitTree node, Space fmt) {
             packageDecl = new J.Package(randomId(), packagePrefix, Markers.EMPTY,
                     convert(cu.getPackageName()), packageAnnotations);
         }
-
         return new J.CompilationUnit(
                 randomId(),
                 fmt,
@@ -912,10 +911,11 @@ public J visitMethodInvocation(MethodInvocationTree node, Space fmt) {
                 singletonList(padRight(new J.Empty(randomId(), sourceBefore(")"), Markers.EMPTY), EMPTY)) :
                 convertAll(node.getArguments(), commaDelim, t -> sourceBefore(")")), Markers.EMPTY);
 
-        Symbol genericSymbol = (jcSelect instanceof JCFieldAccess) ? ((JCFieldAccess) jcSelect).sym : ((JCIdent) jcSelect).sym;
+        Symbol methodSymbol = (jcSelect instanceof JCFieldAccess) ? ((JCFieldAccess) jcSelect).sym :
+                ((JCIdent) jcSelect).sym;
 
         return new J.MethodInvocation(randomId(), fmt, Markers.EMPTY, select, typeParams, name, args,
-                typeMapping.methodInvocationType(jcSelect.type, genericSymbol));
+                typeMapping.methodInvocationType(jcSelect.type, methodSymbol));
     }
 
     @Override
@@ -1701,9 +1701,6 @@ private boolean isEnum(Tree t) {
     }
 
     private <J2 extends @Nullable J> @Nullable JRightPadded<J2> convert(@Nullable Tree t, Function<Tree, Space> suffix) {
-        if (t == null) {
-            return null;
-        }
         return convert(t, suffix, j -> Markers.EMPTY);
     }
 
@@ -1942,9 +1939,9 @@ private static boolean isLombokGenerated(Tree t) {
         }
 
         return isLombokAnnotationType(sym.getQualifiedName().toString()) ||
-                        sym.getDeclarationAttributes().stream()
-                                .map(c -> c.type.toString())
-                                .anyMatch(ReloadableJava8ParserVisitor::isLombokAnnotationType);
+                sym.getDeclarationAttributes().stream()
+                        .map(a -> a.type.toString())
+                        .anyMatch(ReloadableJava8ParserVisitor::isLombokAnnotationType);
     }
 
     private static boolean isLombokAnnotationType(String name) {

rewrite-java-tck/src/main/java/org/openrewrite/java/tree/MethodInvocationTest.java

@@ -17,7 +17,10 @@
 
 import org.junit.jupiter.api.Test;
 import org.openrewrite.ExecutionContext;
+import org.openrewrite.Issue;
 import org.openrewrite.java.JavaIsoVisitor;
+import org.openrewrite.java.JavaParser;
+import org.openrewrite.java.MinimumJava11;
 import org.openrewrite.test.RewriteTest;
 
 import java.util.Optional;
@@ -132,4 +135,28 @@ void m() {
           )
         );
     }
+
+    @Issue("https://github.com/openrewrite/rewrite/issues/5400") // Fails on Java 8, but passes on Java 11 and later
+    @MinimumJava11
+    @Test
+    void methodParameterNamesPresent() {
+        rewriteRun(
+          spec -> spec.parser(JavaParser.fromJavaVersion().classpath("assertj-core")),
+          java(
+            """
+              import static org.assertj.core.api.Assertions.assertThat;
+              class Regular {
+                  void method(String exp, String act) {
+                      assertThat(act).isEqualTo(exp);
+                  }
+              }
+              """,
+            spec -> spec.beforeRecipe(cu -> {
+                J.MethodDeclaration md = (J.MethodDeclaration) cu.getClasses().get(0).getBody().getStatements().get(0);
+                J.MethodInvocation mi = (J.MethodInvocation) md.getBody().getStatements().get(0);
+                assertThat(mi.getMethodType().getParameterNames()).containsExactly("expected");
+            })
+          )
+        );
+    }
 }